• 전기전자학회논문지
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• 제27권3호
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• pp.234-238
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• 2023

본 논문에서는 PVT(process, voltage, and temperature) 변화에 대한 보상기능을 가지는 시간-디지털 변환기(time-to-digital converter : TDC)를 제안한다. 일반적인 지연 라인(delay line) 기반의 TDC는 인버터의 전파 지연을 기반으로 시간을 측정하기 때문에 근본적으로 PVT 변화에 민감하다. 이 논문은 PVT 변화에 의한 전파 지연을 보상하여 TDC의 해상도 변화를 최소화시키는 방법을 제안한다. 또한 넓은 입력 측정 범위(detection range)를 갖기 위해 Cyclic Vernier TDC (CVTDC) 구조를 채택한다. 제안하는 PVT보상 기능의 CVTDC는 45nm CMOS 공정으로 설계되어, 8mW의 전력을 소모하며, 5 ps의 TDC 해상도 및 약 5.1 ns 입력 측정 범위를 갖는다.

• International journal of advanced smart convergence
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• 제5권1호
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• pp.34-46
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• 2016

Networked Control System (NCS) has evolved in the past decade through the advances in communication technology. The problems involved in NCS are broadly classified into two categories namely network issues due to network and control performance due to system network. The network problems are related to bandwidth allocation, scheduling and network security, and the control problems deal with stability analysis and delay compensation. Various delays with variable length occur due to sharing a common network medium. Though most delays are very less and mostly neglected, the network induced delay is significant. It occurs when sensors, actuators, and controllers exchange data packet across the communication network. Networked induced delay arises from sensor to controller and controller to actuator. This paper presents an adaptive delay compensation process for efficient control. Though Smith predictor has been commonly used as dead time compensators, it is not adaptive to match with the stochastic behavior of network characteristics. Time delay adaptive compensation gives an effective control to solve dead time, and creates a virtual environment using the plant model and computed delay which is used to compensate the effect of delay. This approach is simulated using TrueTime simulator that is a Matlab Simulink based simulator facilitates co-simulation of controller task execution in real-time kernels, network transmissions and continuous plant dynamics for NCS. The simulation result is analyzed, and it is confirmed that this control provides good performance.

• KDI Journal of Economic Policy
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• 제33권3호
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• pp.121-161
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• 2011

본 연구에서는 토지수용 관련 보상액 산정과정과 관련한 이해구조를 순차게임모형을 통하여 분석하였다. 우선 공공사업을 추진하는 수용자와 토지를 수용당하는 피수용자 모두가 특정한 조건하에서는 법에서 정하는 정당보상액에 비해서 많은 금액을 보상액으로 책정하고자 하는 유인이 존재할 수 있음을 모형을 통해 도출하였다. 또한 토지수용에 대한 피수용자의 반발 수준을 정하는 모형을 통해 피수용자가 보상금을 더 많이 받기 위해 전략적으로 갈등을 일으킬 유인이 존재함을 보였다. 그리고 이를 통해 과다보상의 문제를 해결하고 정당보상이 이루어지도록 하기 위해서는 수용자와 피수용자가 가지는 인센티브가 보상액 산정에 미치는 영향을 최소화할 필요가 있음을 보였다. 이를 바탕으로 현재의 감정평가제도의 문제점을 살펴보고 관련 제도 개선방향 등을 모색하였다.

• 소성∙가공
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• 제23권7호
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• pp.439-445
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• 2014

Changes in the accuracy of the geometrical shape after a surface treatment are often very large due to the variation of the deformation mechanisms such as edge draw-in and the variation in springback caused by the reduction in the coefficient of friction between the tool and the blank. In the present study, the resulting shape accuracy due to the changes in deformation is quantitatively examined in order to predict the variation and to remove any undesirable additional tool compensation for the center pillar member made from steel with a UTS of 980MPa. The study examines important process parameters that are closely related with the edge draw-in such as the blank holding force, the contact status between the tool and the blank and the friction coefficient. The proposed method is applied within the finite element analysis of the stamping process for tools after a surface treatment and the amount of edge draw-in and flush values are compared between the analysis and experiments. The results demonstrate that the proposed quantification and finite element scheme are applicable to complicated tool compensation procedures and compensation can be designed effectively.

• 전력전자학회논문지
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• 제27권6호
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• pp.481-488
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• 2022

This study proposes compensation methods for the initial position error and torque ripple in vector control of two-phase hybrid stepping motors. Stepping motors have an asymmetrical structure due to misalignment, such as the eccentricity generated by the manufacturing and assembly process. When vector control is applied using the position information measured by an incremental encoder attached to the rotor shaft of such stepping motors, the following problems occur. First, an initial position error occurs during the forced excitation process for the initial rotor position alignment. Second, torque ripple corresponding to the mechanical rotation frequency is generated. In this study, these non-ideal phenomena that occur in vector control of the stepping motor are analyzed, and compensation methods are proposed to eliminate them. The validity of the proposed initial position error and torque ripple compensation methods is verified through experiments on a two-phase hybrid stepping motor drive system.

• 한국응급구조학회지
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• 제26권1호
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• pp.119-127
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• 2022

Purpose: This study aimed to examine the necessity of administrative compensation insurance and claims cases during the emergency medical service process among administrative compensation insurance cases and suggests problems and improvement measures. Methods: We compared the details of administrative compensation insurance claims of 15 cities and provinces, excluding Seoul and Kwangju, from 2017 to 2020 by requesting details disclosure of the comprehensive deduction for administrative compensation in 17 cities and provinces across the country. Results: A total of 69 cases were compensated through the administrative comprehensive compensation deductions. There were 53 cases of damage that occurred at the field stage, 14 cases at the transfer and hospital stage, and two other cases. Conclusion: The 119 paramedics, which are the perpetrators, should be active in field activities and free from the psychological pressure caused by increased workload and litigation. Active compensation administration is required for damage cases occurring in the firefighting activities context.

• 디지털콘텐츠학회 논문지
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• 제10권4호
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• pp.569-578
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• 2009

본 논문에서는 컬러 보정차트를 이용한 디지털 영상의 컬러 보정 알고리즘을 제안한다. 제안된 알고리즘은 기준 컬러 값과 영상으로부터 취득된 컬러 값 사이의 컬러 변환 관계를 계산하기 위하여 별도의 컬러 보정 차트를 이용한다. 기존의 컬러 재현 알고리즘은 취득된 영상에 대한 컬러 스펙트럼 분석 및 디지털 영상의 형성 과정에 대한 모델링 등을 통한 방법을 이용하여 취득된 영상에 대한 컬러를 보정하는 방법을 주로 이용한다. 제안된 알고리즘은 차트로부터 제공되는 기준 영상과 취득된 영상의 컬러 사이의 변환 관계를 이용하여 컬러 보정 과정을 수행한다. 제안된 알고리즘은 두 단계로 수행된다. 컬러 보정의 첫 번째 단계에서는 컬러 차트의 영상을 취득한 다음, 내부의 기준 컬러 값과 차트 영상으로부터 취득된 컬러 값 사이의 변환 관계를 계산한다. 두 번째 단계에서는 계산된 변환 관계를 이용하여 차트 영상과 유사한 조건에서 촬영된 영상에 대한 컬러 보정을 수행한다. 제안된 알고리즘의 성능을 평가하기 위해서 다양한 조건 하에서 실험을 수행하였으며, 이를 일반적인 상용프로그램들의 컬러 보정 성능과 비교 및 평가하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.943-946
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• 2000

Selective laser sintering(SLS) is a solid freeform fabrication process whereby a part is built layerwise by scanning a powder bed. The properties of metal powder are dependent on the heat, it is not easy to do the exact error compensation with analysis and estimation by modeling. This paper suggests that the error is compensated by experimental method and then the accuracy of shape is enhanced by revising of STL file. Also bonding force is measured by an experiment with change of process path.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.804-808
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• 1991

In a transfer line with mass production capability, calibration systems are included in the process as a separate dedicated station. However, this method is not appropriate in an unattended FMC with flexibility. As the FMC produces vesatile parts with small batch sizes, more flexible calibration systems are required. In this paper, a calibration/inspection system suitable for an unattended turning cell is introduced. The system has functions of dimension calibration of parts by touch probes, tool wear compensation, and quality monitoring of parts. Furthermore, characteristics of errors in the system are identified and corresponding compensation methodology is suggested. An operation software was developed for efficient use of the system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(4)
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• pp.167-170
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• 2000

In this paper, we propose the edge compensation algorithm which connects the adjacent edges without losing the information of the skeletons on the edge image. The proposed edge compensation algorithm is composed of succeeding two steps. In the first step, the uplifted image is obtained by applying the uplifting process to the edge image. The next step is to extract the edge image from the uplifted image using the skeleton extraction algorithm. Experimental results show that the proposed method connects the adjacent edges without the distortion of the original edge information compared to the traditional method